[entity] ensure the .related(entities=False) parameter is honored all the way down (closes #2755994)
As of today, such a call will always fill the relation cache by
calling .entities() on every single related rset entry.
As a consequence, the `limit` parameter handling also had to be fixed.
It was bogus in the following ways:
* not used in the related_rql, hence potentially huge database
requests, but also actually
* foolishly used in the .entities()-calling cache routine we now
bypass (this changeset ticket's main topic)
Now:
* we set a limit on the rql expression, and
* forbid caching if given a non-None limit (as we don't want to make
the cache handling code more complicated than it is already)
With this, entity.unrelated gets a better limit implementation (so the
code in related/unrelated is nice and symmetric)
Risk:
* _cw_relation_cache disappears completely, which is good, but this is
Python, so you never know ...
# copyright 2003-2010 LOGILAB S.A. (Paris, FRANCE), all rights reserved.# contact http://www.logilab.fr/ -- mailto:contact@logilab.fr## This file is part of CubicWeb.## CubicWeb is free software: you can redistribute it and/or modify it under the# terms of the GNU Lesser General Public License as published by the Free# Software Foundation, either version 2.1 of the License, or (at your option)# any later version.## CubicWeb is distributed in the hope that it will be useful, but WITHOUT# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS# FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more# details.## You should have received a copy of the GNU Lesser General Public License along# with CubicWeb. If not, see <http://www.gnu.org/licenses/>.""""""fromlogilab.common.testlibimportTestCase,unittest_mainclassImportTC(TestCase):deftest(self):# the minimal test: module is importable...importcubicweb.server.serverimportcubicweb.server.checkintegrityimportcubicweb.server.serverctlif__name__=='__main__':unittest_main()